Displaying publications 141 - 160 of 10357 in total

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  1. Dosimetric features and kinetic parameters of a glass system dosimeter
    Mhareb MHA, Alajerami YSM, Alqahtani M, Alshahri F, Saleh N, Alonizan N, et al.
    Luminescence, 2020 Jun;35(4):525-533.
    PMID: 31883298 DOI: 10.1002/bio.3761
    Lithium borate (LB) glasses doped with dysprosium oxide (Dy2 O3 ) have been prepared by utilizing the conventional melt-quench technique. The prepared glass samples were exposed to 60 Co to check their dosimetric features and kinetic parameters. These features involve glow curves, annealing, fading, reproducibility, minimum detectable dose (MDD), and effective atomic number (Zeff ). Kinetic parameters including the frequency factors and activation energy were also determined using three methods (glow curve analysis, initial rise, and peak shape method) and were thoroughly interpreted. In addition, the incorporation of Dy impurities into LB enhanced the thermoluminescence sensitivity ~170 times. The glow from LB:Dy appeared as a single prominent peak at 190°C. The best annealing proceeding was obtained at 300°C for 30 min. Signal stability was reported for a period of 1 and 3 months with a reduction of 26% and 31%, respectively. The proposed glass samples showed promising dosimeter properties that can be recommended for personal radiation monitoring.
    Matched MeSH terms: Borates/chemistry*; Dysprosium/chemistry*; Glass/chemistry; Lithium Compounds/chemistry*
  2. 2D Graphene oxide (GO) doped p-n type BiOI/Bi2WO6 as a novel composite for photodegradation of bisphenol A (BPA) in aqueous solutions under UV-vis irradiation
    Mengting Z, Kurniawan TA, Yanping Y, Avtar R, Othman MHD
    Mater Sci Eng C Mater Biol Appl, 2020 Mar;108:110420.
    PMID: 31924000 DOI: 10.1016/j.msec.2019.110420
    Bisphenol A (BPA) is a refractory pollutant presents in water body that possesses serious threats to living organisms. To deal with it, we investigate and evaluate the effectiveness of GO@BiOI/Bi2WO6 composite as a novel photocatalyst for BPA removal from aqueous solutions under UV-vis irradiation. To enhance its removal for BPA, the surface of BiOI/Bi2WO6 is modified with graphene oxide (GO). This composite is named as 'GO@BiOI/Bi2WO6'. Changes in its physico-chemical properties after surface modification with GO are characterized by XRD, FTIR, FESEM-EDS, XPS, PL, and BET methods. Optimized conditions of BPA degradation by the composite are determined under identical conditions. Photodegradation pathways of BPA and its removal mechanisms by the same composite are presented. It is obvious that the GO@BiOI/Bi2WO6 has demonstrated its potential as a promising photocatalyst for BPA removal under UV-vis irradiation. About 81% of BPA removal is attained by the GO@BiOI/Bi2WO6 under optimized conditions (10 mg/L of BPA, 0.5 g/L of dose, pH 7 and 5 h of reaction time). The oxidation by-products of BPA degradation include p-hydroquinone or 4-(1-hydroxy-1-methyl-ethyl)-phenol. In spite of its performance, the treated effluents are still unable to meet the maximum discharge limit of <1 mg/L set by national legislation. Therefore, subsequent biological processes are essential to maximize its biodegradation in the wastewater samples before their discharge into waterbody.
    Matched MeSH terms: Benzhydryl Compounds/chemistry*; Carbon/chemistry; Graphite/chemistry*; Phenols/chemistry*
  3. Recent advances of thermal properties of sugar palm lignocellulosic fibre reinforced polymer composites
    Asyraf MRM, Ishak MR, Norrrahim MNF, Nurazzi NM, Shazleen SS, Ilyas RA, et al.
    Int J Biol Macromol, 2021 Dec 15;193(Pt B):1587-1599.
    PMID: 34740691 DOI: 10.1016/j.ijbiomac.2021.10.221
    Biocomposites are materials that are easy to manufacture and environmentally friendly. Sugar palm fibre (SPF) is considered to be an emerging reinforcement candidate that could provide improved mechanical stiffness and strength to the biocomposites. Numerous studies have been recently conducted on sugar palm biocomposites to evaluate their physical, mechanical and thermal properties in various conditions. Sugar palm biocomposites are currently limited to the applications of traditional household products despite their good thermal stability as a prospective substitute candidate for synthetic fibres. Thus, thermal analysis methods such as TGA and DTG are functioned to determine the thermal properties of single fibre sugar palm composites (SPCs) in thermoset and thermoplastic matrix as well as hybrid SPCs. The biocomposites showed a remarkable change considering thermal stability by varying the individual fibre compositions and surface treatments and adding fillers and coupling agents. However, literature that summarises the thermal properties of sugar palm biocomposites is unavailable. Particularly, this comprehensive review paper aims to guide all composite engineers, designers, manufacturers and users on the selection of suitable biopolymers for sugar palm biocomposites for thermal applications, such as heat shields and engine components.
    Matched MeSH terms: Biocompatible Materials/chemistry*; Lignin/chemistry*; Polymers/chemistry*; Arecaceae/chemistry*
  4. Comprehensive exploration of natural degradation of poly(lactic acid) blends in various degradation media: A review
    Rosli NA, Karamanlioglu M, Kargarzadeh H, Ahmad I
    Int J Biol Macromol, 2021 Sep 30;187:732-741.
    PMID: 34358596 DOI: 10.1016/j.ijbiomac.2021.07.196
    Poly(lactic acid) (PLA), a bio-based polyester, has been extensively investigated in the recent past owing to its excellent mechanical properties. Several studies have been conducted on PLA blends, with a focus on improving the brittleness of PLA to ensure its suitability for various applications. However, the increasing use of PLA has increased the contamination of PLA-based products in the environment because PLA remains intact even after three years at sea or in soil. This review focuses on analyzing studies that have worked on improving the degradation properties of PLA blends and studies how other additives affect degradation by considering different degradation media. Factors affecting the degradation properties, such as surface morphology, water uptake, and crystallinity of PLA blends, are highlighted. In natural, biotic, and abiotic media, water uptake plays a crucial role in determining biodegradation rates. Immiscible blends of PLA with other polymer matrices cause phase separation, increasing the water absorption. The susceptibility of PLA to hydrolytic and enzymatic degradation is high in the amorphous region because it can be easily penetrated by water. It is essential to study the morphology, water absorption, and structural properties of PLA blends to predict the biodegradation properties of PLA in the blends.
    Matched MeSH terms: Enzymes/chemistry*; Polyesters/chemistry*; Polymers/chemistry*; Water/chemistry*
  5. Novel controlled ionic gelation strategy for chitosan nanoparticles preparation using TPP-β-CD inclusion complex
    Pant A, Negi JS
    Eur J Pharm Sci, 2018 Jan 15;112:180-185.
    PMID: 29191520 DOI: 10.1016/j.ejps.2017.11.020
    The aim of this study was to develop a novel controlled ionic gelation strategy for chitosan nanoparticle preparation to avoid particle aggregation tendency associated with conventional ionic gelation process. In this study inclusion complexation behaviour of sodium tripolyphosphate (TPP) with beta cyclodextrin (β-CD) has been investigated. The TPP-β-CD inclusion complex was characterized by FT-IR, XRD and DSC techniques. The complexation behaviour was also investigated by molecular docking study. The results showed that the TPP molecule formed inclusion complex with β-CD. Further, TPP-β-CD inclusion complex was used to prepare chitosan nanoparticles. The chitosan nanoparticles based on TPP-β-CD inclusion complex had smaller size of 104.2nm±0.608, good PDI value of 0.346±0.016 and acceptable zeta potential of +27.33mV±0.416. The surface characteristics of chitosan nanoparticles were also observed with transmission electron microscopy. Results indicates that TPP-β-CD inclusion complex can be used for the formation of chitosan nanoparticles with smaller and more uniform particle size in comparison to conventional TPP based chitosan nanoparticles.
    Matched MeSH terms: Polyphosphates/chemistry*; beta-Cyclodextrins/chemistry*; Chitosan/chemistry*; Nanoparticles/chemistry*
  6. Polymer blend of PLA/PHBV based bionanocomposites reinforced with nanocrystalline cellulose for potential application as packaging material
    Dasan YK, Bhat AH, Ahmad F
    Carbohydr Polym, 2017 Feb 10;157:1323-1332.
    PMID: 27987839 DOI: 10.1016/j.carbpol.2016.11.012
    The current research discusses the development of poly (lactic acid) (PLA) and poly-(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) reinforced nanocrystalline cellulose bionanocomposites. The nanocrystalline cellulose was derived from waste oil palm empty fruit bunch fiber by acid hydrolysis process. The resulting nanocrystalline cellulose suspension was then surface functionalized by TEMPO-mediated oxidation and solvent exchange process. Furthermore, the PLA/PHBV/nanocrystalline cellulose bionanocomposites were produced by solvent casting method. The effect of the addition of nanocrystalline cellulose on structural, morphology, mechanical and barrier properties of bionanocomposites was investigated. The results revealed that the developed bionanocomposites showed improved mechanical properties and decrease in oxygen permeability rate. Therefore, the developed bio-based composite incorporated with an optimal composition of nanocrystalline cellulose exhibits properties as compared to the polymer blend.
    Matched MeSH terms: Cellulose/chemistry*; Polyesters/chemistry*; Nanoparticles/chemistry*; Nanocomposites/chemistry*
  7. Fulltext Plants of the Genus Zingiber as a Source of Bioactive Phytochemicals: From Tradition to Pharmacy
    Sharifi-Rad M, Varoni EM, Salehi B, Sharifi-Rad J, Matthews KR, Ayatollahi SA, et al.
    Molecules, 2017 Dec 04;22(12).
    PMID: 29207520 DOI: 10.3390/molecules22122145
    Plants of the genus Zingiber (Family Zingiberaceae) are widely used throughout the world as food and medicinal plants. They represent very popular herbal remedies in various traditional healing systems; in particular, rhizome of Zingiber spp. plants has a long history of ethnobotanical uses because of a plethora of curative properties. Antimicrobial activity of rhizome essential oil has been extensively confirmed in vitro and attributed to its chemical components, mainly consisting of monoterpene and sesquiterpene hydrocarbons such as α-zingiberene, ar-curcumene, β-bisabolene and β-sesquiphellandrene. In addition, gingerols have been identified as the major active components in the fresh rhizome, whereas shogaols, dehydrated gingerol derivatives, are the predominant pungent constituents in dried rhizome. Zingiber spp. may thus represent a promising and innovative source of natural alternatives to chemical food preservatives. This approach would meet the increasing concern of consumers aware of the potential health risks associated with the conventional antimicrobial agents in food. This narrative review aims at providing a literature overview on Zingiber spp. plants, their cultivation, traditional uses, phytochemical constituents and biological activities.
    Matched MeSH terms: Food Preservatives/chemistry; Oils, Volatile/chemistry; Zingiberaceae/chemistry*; Phytochemicals/chemistry*
  8. Synergistic interactions between lecithin and fruit wax in oleogel formation
    Okuro PK, Tavernier I, Bin Sintang MD, Skirtach AG, Vicente AA, Dewettinck K, et al.
    Food Funct, 2018 Mar 01;9(3):1755-1767.
    PMID: 29508864 DOI: 10.1039/c7fo01775h
    In this study, the effect of lecithin (LEC) on the crystallization and gelation of fruit wax (FW) with sunflower oil was researched. A synergistic effect on the gel strength was observed at FW : LEC ratios of 75 : 25 and 50 : 50, compared to the corresponding single component formulations (100 : 0 and 0 : 100). Even below the critical gelling concentration (Cg) of FW, the addition of lecithin enabled gel formation. Lecithin affected the thermal behavior of the structure by delaying both crystallization and gel formation. The phospholipid acted as a crystal habit modifier changing the microstructure of the oleogel, as was observed by polarized light microscopy. Cryo-scanning electron microscopy revealed a similar platelet-like arrangement for both FW as a single oleogelator and FW in combination with LEC. However, a denser structure could be observed in the FW : LEC oleogelator mixture. Both the oil-binding capacity and the thixotropic recovery were enhanced upon lecithin addition. These improvements were attributed to the hydrogen bonding between FW and LEC, as suggested by Raman spectroscopy. We hypothesized that lecithin alters the molecular assembly properties of the FW due to the interactions between the polar moieties of the oleogelators, which consequently impacts the hydrophobic tail (re)arrangement in gelator-gelator and solvent-gelator interactions. The lipid crystal engineering approach followed here offered prospects of obtaining harder self-standing structures at a lower oleogelator concentration. These synergistic interactions provide an opportunity to reduce the wax concentration and, as such, the waxy mouthfeel without compromising the oleogel properties.
    Matched MeSH terms: Fruit/chemistry; Organic Chemicals/chemistry; Waxes/chemistry*; Lecithins/chemistry*
  9. Bio-waste corn-cob cellulose supported poly(hydroxamic acid) copper complex for Huisgen reaction: Waste to wealth approach
    Mandal BH, Rahman ML, Yusoff MM, Chong KF, Sarkar SM
    Carbohydr Polym, 2017 Jan 20;156:175-181.
    PMID: 27842811 DOI: 10.1016/j.carbpol.2016.09.021
    Corn-cob cellulose supported poly(hydroxamic acid) Cu(II) complex was prepared by the surface modification of waste corn-cob cellulose through graft copolymerization and subsequent hydroximation. The complex was characterized by IR, UV, FESEM, TEM, XPS, EDX and ICP-AES analyses. The complex has been found to be an efficient catalyst for 1,3-dipolar Huisgen cycloaddition (CuAAC) of aryl/alkyl azides with a variety of alkynes as well as one-pot three-components reaction in the presence of sodium ascorbate to give the corresponding cycloaddition products in up to 96% yield and high turn over number (TON 18,600) and turn over frequency (TOF 930h-1) were achieved. The complex was easy to recover from the reaction mixture and reused six times without significant loss of its catalytic activity.
    Matched MeSH terms: Cellulose/chemistry*; Copper/chemistry*; Zea mays/chemistry*; Hydroxamic Acids/chemistry*
  10. Cassava/sugar palm fiber reinforced cassava starch hybrid composites: Physical, thermal and structural properties
    Edhirej A, Sapuan SM, Jawaid M, Zahari NI
    Int J Biol Macromol, 2017 Aug;101:75-83.
    PMID: 28288881 DOI: 10.1016/j.ijbiomac.2017.03.045
    A hybrid composite was prepared from cassava bagasse (CB) and sugar palm fiber (SPF) using casting technique with cassava starch (CS) as matrix and fructose as a plasticizer. Different loadings of SPF (2, 4, 6 and 8% w/w of dry starch) were added to the CS/CB composite film containing 6% CB. The addition of SPF significantly influenced the physical properties. It increased the thickness while decreasing the density, water content, water solubility and water absorption. However, no significant effect was noticed on the thermal properties of the hybrid composite film. The incorporation of SPF increased the relative crystallinity up to 47%, compared to 32% of the CS film. SEM micrographs indicated that the filler was incorporated in the matrix. The film with a higher concentration of SPF (CS-CB/SPF8) showed a more heterogeneous surface. It could be concluded that the incorporation of SPF led to changes in cassava starch film properties, potentially affecting the film performances.
    Matched MeSH terms: Manihot/chemistry*; Starch/chemistry*; Water/chemistry; Arecaceae/chemistry*
  11. Relative Humidity Cycling: Implications on the Stability of Moisture-Sensitive Drugs in Solid Pharmaceutical Products
    Veronica N, Heng PWS, Liew CV
    Mol Pharm, 2023 Feb 06;20(2):1072-1085.
    PMID: 36480246 DOI: 10.1021/acs.molpharmaceut.2c00812
    The stability of a moisture-sensitive drug in tablet formulations depends particularly on the environment's relative humidity (RH) and the products' prior exposure to moisture. This study was designed to understand drug stability in relation to the moisture interaction of the excipients, moisture history of the tablets, and RH of the environment. The stability study was performed on tablets containing acetylsalicylic acid (ASA), formulated with common pharmaceutical excipients like native maize starch, microcrystalline cellulose (MCC), partially pregelatinized maize starch (PGS), dicalcium phosphate dihydrate (DCP), lactose, and mannitol. The tablets were subjected to storage conditions with RH cycling alternating between 53% and 75%. Results were also compared to tablets stored at a constant RH of 53% or 75%. The excipients demonstrated marked differences in their interactions with moisture. They could be broadly grouped as excipients with RH-dependent moisture content (native maize starch, MCC, and PGS) and RH-independent moisture content (DCP, lactose, and mannitol). As each excipient interacted differently with moisture, degradation of ASA in the tablets depended on the excipients' ability to modulate the moisture availability for degradation. The lowest ASA degradation was observed in tablets formulated with low moisture content water-soluble excipients, such as lactose and mannitol. The impact of RH cycling on ASA stability was apparent in tablets containing native maize starch, MCC, PGS, or DCP. These findings suggested that the choice of excipients influences the effect of moisture history on drug stability. The results from studies investigating moisture interaction of excipients and drug stability are valuable to understanding the inter-relationship between excipients, moisture history, and drug stability.
    Matched MeSH terms: Aspirin/chemistry; Mannitol/chemistry; Starch/chemistry; Tablets/chemistry
  12. Carbon dioxide sequestration of iron ore mining waste under low-reaction condition of a direct mineral carbonation process
    Kusin FM, Hasan SNMS, Molahid VLM, Yusuff FM, Jusop S
    Environ Sci Pollut Res Int, 2023 Feb;30(9):22188-22210.
    PMID: 36282383 DOI: 10.1007/s11356-022-23677-3
    Mining waste that is rich in iron-, calcium- and magnesium-bearing minerals can be a potential feedstock for sequestering CO2 by mineral carbonation. This study highlights the utilization of iron ore mining waste in sequestering CO2 under low-reaction condition of a mineral carbonation process. Alkaline iron mining waste was used as feedstock for aqueous mineral carbonation and was subjected to mineralogical, chemical, and thermal analyses. A carbonation experiment was performed at ambient CO2 pressure, temperature of 80 °C at 1-h exposure time under the influence of pH (8-12) and particle size (
    Matched MeSH terms: Calcium Carbonate/chemistry; Carbonates/chemistry; Minerals/chemistry; Silicates/chemistry
  13. Fulltext Optimisation of Epoxide Ring-Opening Reaction for the Synthesis of Bio-Polyol from Palm Oil Derivative Using Response Surface Methodology
    Kamairudin N, Hoong SS, Abdullah LC, Ariffin H, Biak DRA
    Molecules, 2021 Jan 27;26(3).
    PMID: 33513686 DOI: 10.3390/molecules26030648
    The development of bio-polyol from vegetable oil and its derivatives is gaining much interest from polyurethane industries and academia. In view of this, the availability of methyl oleate derived from palm oil, which is aimed at biodiesel production, provides an excellent feedstock to produce bio-polyol for polyurethane applications. In this recent study, response surface methodology (RSM) with a combination of central composite rotatable design (CCRD) was used to optimise the reaction parameters in order to obtain a maximised hydroxyl value (OHV). Three reaction parameters were selected, namely the mole ratio of epoxidised methyl oleate (EMO) to glycerol (1:5-1:10), the amount of catalyst loading (0.15-0.55%) and reaction temperature (90-150 °C) on a response variable as the hydroxyl value (OHV). The analysis of variance (ANOVA) indicated that the quadratic model was significant at 98% confidence level with (p-value > 0.0001) with an insignificant lack of fit and the regression coefficient (R2) was 0.9897. The optimum reaction conditions established by the predicted model were: 1:10 mole ratio of EMO to glycerol, 0.18% of catalyst and 120 °C reaction temperature, giving a hydroxyl value (OHV) of 306.190 mg KOH/g for the experimental value and 301.248 mg KOH/g for the predicted value. This result proves that the RSM model is capable of forecasting the relevant response. FTIR analysis was employed to monitor the changes of functional group for each synthesis and the confirmation of this finding was analysed by NMR analysis. The viscosity and average molecular weight (MW) were 513.48 mPa and 491 Da, respectively.
    Matched MeSH terms: Epoxy Compounds/chemistry*; Glycerol/chemistry; Polymers/chemistry*; Polyurethanes/chemistry
  14. Fulltext Exceedingly biocompatible and thin-layered reduced graphene oxide nanosheets using an eco-friendly mushroom extract strategy
    Muthoosamy K, Bai RG, Abubakar IB, Sudheer SM, Lim HN, Loh HS, et al.
    Int J Nanomedicine, 2015;10:1505-19.
    PMID: 25759577 DOI: 10.2147/IJN.S75213
    PURPOSE: A simple, one-pot strategy was used to synthesize reduced graphene oxide (RGO) nanosheets by utilizing an easily available over-the-counter medicinal and edible mushroom, Ganoderma lucidum.

    METHODS: The mushroom was boiled in hot water to liberate the polysaccharides, the extract of which was then used directly for the reduction of graphene oxide. The abundance of polysaccharides present in the mushroom serves as a good reducing agent. The proposed strategy evades the use of harmful and expensive chemicals and avoids the typical tedious reaction methods.

    RESULTS: More importantly, the mushroom extract can be easily separated from the product without generating any residual byproducts and can be reused at least three times with good conversion efficiency (75%). It was readily dispersible in water without the need of ultrasonication or any surfactants; whereas 5 minutes of ultrasonication with various solvents produced RGO which was stable for the tested period of 1 year. Based on electrochemical measurements, the followed method did not jeopardize RGO's electrical conductivity. Moreover, the obtained RGO was highly biocompatible to not only colon (HT-29) and brain (U87MG) cancer cells, but was also viable towards normal cells (MRC-5).

    CONCLUSION: Besides being eco-friendly, this mushroom based approach is easily scalable and demonstrates remarkable RGO stability and biocompatibility, even without any form of functionalization.

    Matched MeSH terms: Graphite/chemistry*; Oxides/chemistry*; Nanostructures/chemistry*; Green Chemistry Technology
  15. Fulltext Formation of silver microbelt structures by laser irradiation of silver nanoparticles in ethanol
    Zamiri R, Zakaria A, Husin MS, Wahab ZA, Nazarpour FK
    Int J Nanomedicine, 2011;6:2221-4.
    PMID: 22114485 DOI: 10.2147/IJN.S23830
    In the present work, we prepared silver nanoparticles by laser ablation of pure silver plate in ethanol and then irradiated the silver nanoparticles using a 532 nm Q-switched Nd:YAG pulsed laser. Transmission electron microscopic images of the sample after irradiation clearly showed formation of big structures, such as microrods and microbelts in ethanol. The obtained microbelts had a width of about 0.166 μm and a length of 1.472 μm. The reason for the formation of such a big structure is the tendency of the nanoparticles to aggregate in ethanol before irradiation, which causes fusion of the nanoparticles.
    Matched MeSH terms: Ethanol/chemistry*; Colloids/chemistry; Silver/chemistry*; Metal Nanoparticles/chemistry*
  16. Fulltext Synthesis and characterization of the inclusion complex of dicationic ionic liquid and β-cyclodextrin
    Subramaniam P, Mohamad S, Alias Y
    Int J Mol Sci, 2010 Sep 28;11(10):3675-85.
    PMID: 21152293 DOI: 10.3390/ijms11103675
    The supramolecular structure of the inclusion complex of β-cyclodextrin (β-CD) with 1,1',2,2'-tetramethyl-3,3'-(p-phenylenedimethylene) diimidazolium dibromide (TetraPhimBr), a dicationic ionic liquid, has been investigated. The inclusion complex with 1:1 molar ratio was prepared by a kneading method. Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD) analysis, (1)H NMR and thermogravimetric analysis (TGA) confirmed the formation of the inclusion complex. The results showed that the host-guest system is a fine crystalline powder. The decomposition temperature of the inclusion complex is lower than that of its parent molecules, TetraPhimBr and β-CD individually.
    Matched MeSH terms: beta-Cyclodextrins/chemistry*; Ionic Liquids/chemistry*; Chemistry Techniques, Synthetic/methods
  17. Stability of Bioactive Compounds and Antioxidant Activities of Kenaf Seed Oil-in-Water Nanoemulsions under Different Storage Temperatures
    Cheong AM, Tan CP, Nyam KL
    J Food Sci, 2018 Oct;83(10):2457-2465.
    PMID: 30178877 DOI: 10.1111/1750-3841.14332
    Kenaf seed oil-in-water nanoemulsions (NANO) stabilized by sodium caseinate (SC), beta-cyclodextrin (β-CD), and Tween 20 (T20) have been optimized and shown to improve in vitro bioaccessibility and physicochemical stability in the previous study. The main objective of this study was to evaluate the stability of bioactive compounds and antioxidants in the NANO during storage at different temperatures (4 °C, 25 °C, and 40 °C). An evaluation of the antioxidant activities of each emulsifier showed that SC had good scavenging capability with 97.6% ABTS radical scavenging activity. Therefore, SC which was used as one of the main emulsifiers could further enhanced the antioxidant activity of NANO. At week 8 of storage, NANO that stored at 4 °C had maintained the best bioactive compounds stability and antioxidant activities with 90% retention of vitamin E and 65% retention of phytosterols. These results suggested that 4 °C would be the most suitable storage temperature for NANO containing naturally present vitamin E and phytosterols. From the accelerated storage results at 40 °C, NANO containing vitamin E and phytosterols had maintained half of its initial concentration until week 4 and week 2 of storage, which is equivalent to 16 weeks and 8 weeks of storage at room temperature, respectively.

    PRACTICAL APPLICATION: The results of this study provide a better understanding on the stability of bioactive compounds and antioxidant activities in oil-in-water nanoemulsions that stabilized by similar ternary emulsifiers during storage at different temperatures. In addition, this study could be used as a predictive model to estimate the shelf life of bioactive compounds encapsulated in the form of nanoemulsions.

    Matched MeSH terms: Antioxidants/chemistry*; Emulsions/chemistry*; Phytosterols/chemistry; Plant Oils/chemistry*; Polysorbates/chemistry; Seeds/chemistry; Vitamin E/chemistry; Hibiscus/chemistry*; Emulsifying Agents/chemistry; beta-Cyclodextrins/chemistry
  18. Fulltext A comparison in mechanical properties of cermets of calcium silicate with Ti-55Ni and Ti-6Al-4V alloys for hard tissues replacement
    Ataollahi Oshkour A, Pramanik S, Shirazi SF, Mehrali M, Yau YH, Abu Osman NA
    ScientificWorldJournal, 2014;2014:616804.
    PMID: 25538954 DOI: 10.1155/2014/616804
    This study investigated the impact of calcium silicate (CS) content on composition, compressive mechanical properties, and hardness of CS cermets with Ti-55Ni and Ti-6Al-4V alloys sintered at 1200°C. The powder metallurgy route was exploited to prepare the cermets. New phases of materials of Ni16Ti6Si7, CaTiO3, and Ni31Si12 appeared in cermet of Ti-55Ni with CS and in cermet of Ti-6Al-4V with CS, the new phases Ti5Si3, Ti2O, and CaTiO3, which were emerged during sintering at different CS content (wt%). The minimum shrinkage and density were observed in both groups of cermets for the 50 and 100 wt% CS content, respectively. The cermets with 40 wt% of CS had minimum compressive Young's modulus. The minimum of compressive strength and strain percentage at maximum load were revealed in cermets with 50 and 40 wt% of CS with Ti-55Ni and Ti-6Al-4V cermets, respectively. The cermets with 80 and 90 wt% of CS showed more plasticity than the pure CS. It concluded that the composition and mechanical properties of sintered cermets of Ti-55Ni and Ti-6Al-4V with CS significantly depend on the CS content in raw cermet materials. Thus, the different mechanical properties of the cermets can be used as potential materials for different hard tissues replacements.
    Matched MeSH terms: Bone Cements/chemistry*; Nickel/chemistry*; Titanium/chemistry*; Calcium Compounds/chemistry*; Silicates/chemistry*; Bone Substitutes/chemistry*
  19. Fulltext Optimization of natural lipstick formulation based on pitaya (Hylocereus polyrhizus) seed oil using D-optimal mixture experimental design
    Kamairudin N, Gani SS, Masoumi HR, Hashim P
    Molecules, 2014;19(10):16672-83.
    PMID: 25325152 DOI: 10.3390/molecules191016672
    The D-optimal mixture experimental design was employed to optimize the melting point of natural lipstick based on pitaya (Hylocereus polyrhizus) seed oil. The influence of the main lipstick components-pitaya seed oil (10%-25% w/w), virgin coconut oil (25%-45% w/w), beeswax (5%-25% w/w), candelilla wax (1%-5% w/w) and carnauba wax (1%-5% w/w)-were investigated with respect to the melting point properties of the lipstick formulation. The D-optimal mixture experimental design was applied to optimize the properties of lipstick by focusing on the melting point with respect to the above influencing components. The D-optimal mixture design analysis showed that the variation in the response (melting point) could be depicted as a quadratic function of the main components of the lipstick. The best combination of each significant factor determined by the D-optimal mixture design was established to be pitaya seed oil (25% w/w), virgin coconut oil (37% w/w), beeswax (17% w/w), candelilla wax (2% w/w) and carnauba wax (2% w/w). With respect to these factors, the 46.0 °C melting point property was observed experimentally, similar to the theoretical prediction of 46.5 °C. Carnauba wax is the most influential factor on this response (melting point) with its function being with respect to heat endurance. The quadratic polynomial model sufficiently fit the experimental data.
    Matched MeSH terms: Chemistry, Pharmaceutical; Cosmetics/chemistry*; Plant Oils/chemistry*; Seeds/chemistry*; Waxes/chemistry*; Cactaceae/chemistry*
  20. Fulltext Optimization of reflux conditions for total flavonoid and total phenolic extraction and enhanced antioxidant capacity in Pandan (Pandanus amaryllifolius Roxb.) using response surface methodology
    Ghasemzadeh A, Jaafar HZ
    ScientificWorldJournal, 2014;2014:523120.
    PMID: 25147852 DOI: 10.1155/2014/523120
    Response surface methodology was applied to optimization of the conditions for reflux extraction of Pandan (Pandanus amaryllifolius Roxb.) in order to achieve a high content of total flavonoids (TF), total phenolics (TP), and high antioxidant capacity (AC) in the extracts. Central composite experimental design with three factors and three levels was employed to consider the effects of the operation parameters, including the methanol concentration (MC, 40%-80%), extraction temperature (ET, 40-70°C), and liquid-to-solid ratio (LS ratio, 20-40 mL/g) on the properties of the extracts. Response surface plots showed that increasing these operation parameters induced the responses significantly. The TF content and AC could be maximized when the extraction conditions (MC, ET, and LS ratio) were 78.8%, 69.5°C, and 32.4 mL/g, respectively, whereas the TP content was optimal when these variables were 75.1%, 70°C, and 31.8 mL/g, respectively. Under these optimum conditions, the experimental TF and TP content and AC were 1.78, 6.601 mg/g DW, and 87.38%, respectively. The optimized model was validated by a comparison of the predicted and experimental values. The experimental values were found to be in agreement with the predicted values, indicating the suitability of the model for optimizing the conditions for the reflux extraction of Pandan.
    Matched MeSH terms: Antioxidants/chemistry*; Flavonoids/chemistry*; Phenols/chemistry*; Plant Extracts/chemistry*; Pandanaceae/chemistry*; Phytochemicals/chemistry
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